Ectoparasites are organisms that live on the exterior of a host, feeding on its tissues or bodily fluids. Common examples include fleas, ticks, and lice, which can cause discomfort and transmit diseases to their hosts, including humans and animals. These parasites can significantly impact the health of their hosts, leading to issues such as skin irritation, allergic reactions, and even severe infections. Understanding ectoparasites is crucial for effective management and prevention, especially in veterinary and public health contexts.